chore: bump ruff from 0.12.3 to 0.15.6

Bumps [ruff](https://github.com/astral-sh/ruff) from 0.12.3 to 0.15.6.
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](astral-sh/ruff@0.12.3...0.15.6)

---
updated-dependencies:
- dependency-name: ruff
  dependency-version: 0.15.6
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -50,7 +50,7 @@ dev = [
     "pytest<9.0.0,>=7.1.3",
     "mypy<1.17,>=0.982",
     "pytest-cov<7,>=4",
-    "ruff<0.12.4,>=0.5.1",
+    "ruff>=0.5.1,<0.15.7",
     "types-requests<3.0.0.0,>=2.32.4.20250611",
     "types-python-dateutil>=2.9.0.20250809",
     "freezegun>=1.5.5",